Check valve



Jiy 2, 1940.

CHECK VALVE Filed Oct. 13, 1936 WITNESS.

W B IHINVEQTOR.

ATTORNEY `Patented July 2, 1940 UNITED STATES PATENT DFFICE 1 Claim.

The invention relates to a check valve which is placed in a line of pipeand may be used in either a horizontal position or a vertical position.The movable valve is made to slide a considerable distance and is soconstructed that it will never clog or be prevented from sliding and themain object of this valve is to eliminateA all chattering of the movablevalve thus making the valve of long life and very eflcient. Anotherobject of l0, this check valve is to have a pipe union at each end sothat the' same can be removed from its connections in a pipe linewithout disturbing the pipe.

To describe the invention so that others versed l5 in the art to whichit pertains can make and use the same it is illustrated on theaccompanying sheet of drawings, forming a part of this specification andin which:

Figure l is a side elevation of a valve constructed in accordance withmy invention; Figure 2 is a longitudinal sectional view of the sameshowing the valve in a closed position; Figure 3 Vis a similar viewshowing the valve in an open position with some modifications inconstruction; Figure 4 is a sectional view taken on line 4 4 of Figure3, and Figure 5 is a sectional view taken on line 5-5 of Figure 3.

As clearly illustrated the valve casing 6 is made of the desired sizeand length and is provided at each end with screw threads to receive theouter members I of the unions whose inner members 8 are screwed to theend of the pipes 9. The outside of the valve casing 6 is preferablyprovided with one or more arrows Il] to indicate in what direction thefluid is free to flow.

The movable valve is constructed of a tubular portion I I which is madeto freely slide in a hole I2 provided in the valve cage I3 which has atone end the outwardly extending flange I4 tightly clamped between theinner member 8 of the union and the end of the valve casing 6. The outermember 1 of the union is tightly screwed onto the valve casing 6 toprevent any leakage between the parts.

cage I3 is provided with a valve seat I5 arranged to be engaged by thevalve cap I6 rigidly secured to the one end of the tubular portion I I,the remaining end of the tubular portion II being provided with ashoulder I7 to serve as a stop against the one end of the valve cage I3.

The hollow part of the tubular portion Il ex- -tends to a short distancefrom the valve cap I6 at I8 and is open at the other end. A plurality ofholes I9 are shown through the tubular portion I I a considerabledistance from the valve The other end of the valve` cap I6 and librelwasher 20 which form a free passage for the uid within the tubularportion Vto enter the interior of the valve casing 6 when the valve isin a considerable open position as shown in Figure 3. The valve cap|6-is prefer- 3 ably provided with a libre washer 20.

valve casing 6 can be removed from the pipe line ,10g

without in the least disturbing the pipes 9 after the outer members 'Ihave been screwed loose or disconnected from the valve casing 6.

It will be understood that the valve cage I3 and the movable partstherein are replaced when- I5 ever the parts become worn or leaky. Asshown in Figure 3 a very light coiled expanding spring 2| may beprovided as shown to normally hold the valve in a closed position.

In operation the check valve is placed in proper 20 position in the pipeline to permit the fluid Within the pipe line to flow freely in thedirection indicated by the arrows in Figures 2 and 3 and prevent anyflow inthe opposite direction. From long experience it has been foundthat when 25 check valves are placed in a pipe linecontaining pressureand a liquid is depended upon to operate the check valve, that the valvewill under certain conditions chatter and such chattering of themovable-valve will soon wear the parts and 30 cause the valve to leak.The construction and operation of this valve is such that there is neverthe slightest amount of chattering produced and for that reason partscomprising the valve and cage require replacement very seldom. 35 Thetubular portion II fits loosely in the hole I2 so that if the valve isunseated only slightly and not suilicient to have the holes I9 passbeyond the seat I5 a small amount of fluid may pass between the tubularportion II and the wall of hole I2 and out between the valve seat I5 andthe valve cap I6; and when a portion of the holes I9 pass the valve seatI5 a Agreater amount of fluid may pass into the interior of valve casing6, and when the holes I9 are entirely beyond the 45 valve seat I5 theentire amount of fluid passing through the pipe line 9 is free to passthe valve. Obviously as soon as there is any reverse flow of fluid inthe pipe line 9 the valve will be moved to a closed position. 50

Having thus fully described my invention what I desire to secure byLetters Patent of the United States is:

In combination, a casing provided at each end with a male screw thread,flanges secured at each 55 l end of said casing provided with screwthreads to t the screw threads on the casing, said casing forming aunion between said two flanges, one end of said casing provided with abeveled circular surface, a tubular valve cage to llt loosely withinsaid casing to provide an annular space v between the cage and innerwall of the casing, said cage provided with a beveled circular flangeclamped against the beveled ciigcular surface of said casing by theadjacent one of said anges,

loosely Within the smaller bore of said valve cage to provide forlimited passage of fluid on initial opening movement of said valve andprovided on its end opposite the valve with an outwardly extendingflange of greater diameter than the smaller bore of said valve cage toengage 'said shoulder to limit movement of said valve cage in onedirection and suitable openings through the wall of said hollow valvestem a considerable distance from the Valveto form communication betweenthe interior of said hollow stem and the interior of said casing whensaid valve is opened a sucient distance to expose said openings abovethe seat.

WALTER B. HUTCHINGS.

